Cheap flights from Illinois to Ontario (ONT) from $53

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/23. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
ORD — ONT
Apr 3 — Apr 101

How far in advance should I book a flight from Illinois to Ontario?

Travelers have found it’s best to book a flight 49 days in advance to save up to 54% compared to booking the same week of travel. As your travel date approaches, the cost of this flight route may potentially increase. While opting to book 49 days out may not be an option for all, there are still additional ways to secure a deal in the near future. You might find a flight from Illinois to Ontario 1-2 weeks in advance for as low as $277, or $498 for flights within the next 24 hours.

What is the cheapest month to fly from Illinois to Ontario?

Due to multiple factors, expect to potentially pay more when booking in June. For low rates, January can be a great choice for travel to Ontario. Flights to Ontario from Illinois in January are about $296 on average during January, but can be found for as low as $90.

When is the cheapest time to fly from Illinois to Ontario (IL - ONT)?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Illinois to Ontario as you normally would.

Cheap Frontier flights from Illinois to Ontario

Explore cheap flight options specifically provided by Frontier for the route between Illinois and Ontario. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 3,228,805 searches. Data last updated March 29, 2024.
Take a peek at the cheapest Frontier flights we've detected traveling from Illinois to Ontario. Deals update often to give you more flight options matching your criteria
Wed 5/158:04 pmSTL - ONT
1 stop5h 55mFrontier
Fri 5/1712:59 amONT - STL
1 stop6h 26mFrontier
Deal found 3/27$76
Sat 4/208:04 pmSTL - ONT
1 stop5h 55mFrontier
Fri 4/2612:55 amONT - STL
1 stop6h 52mFrontier
Deal found 3/28$89
Sat 4/279:29 pmMDW - ONT
1 stop11h 02mFrontier
Sat 5/47:26 amONT - MDW
1 stop11h 13mFrontier
Deal found 3/28$90
Tue 4/305:01 amMDW - ONT
1 stop10h 00mFrontier
Tue 4/3010:49 pmONT - MDW
1 stop10h 47mFrontier
Deal found 3/28$91
Thu 5/1610:22 pmMDW - ONT
1 stop27h 37mFrontier
Wed 5/222:35 pmONT - MDW
1 stop28h 52mFrontier
Deal found 3/28$94
Sat 4/2710:59 pmMDW - ONT
1 stop10h 04mFrontier
Fri 5/312:55 amONT - MDW
1 stop17h 44mFrontier
Deal found 3/28$95
Sat 4/2710:30 amMDW - ONT
1 stop15h 29mFrontier
Tue 4/3010:49 pmONT - MDW
1 stop10h 47mFrontier
Deal found 3/28$96
Sat 4/2710:30 amMDW - ONT
1 stop15h 29mFrontier
Mon 4/2912:59 amONT - MDW
1 stop8h 39mFrontier
Deal found 3/28$97
Mon 5/209:10 pmMDW - ONT
1 stop13h 54mFrontier
Tue 5/2112:59 amONT - MDW
1 stop8h 10mFrontier
Deal found 3/28$98

Cheap American Airlines flights from Illinois to Ontario

Explore cheap flight options specifically provided by American Airlines for the route between Illinois and Ontario. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 3,228,805 searches. Data last updated March 29, 2024.
Take a gander at the lowest prices we've found on American Airlines flights from Illinois to Ontario. Deals are refreshing constantly so come back soon for more options.
Fri 4/51:20 pmORD - ONT
1 stop9h 22mAmerican Airlines
Sun 4/72:53 pmONT - ORD
1 stop6h 15mAmerican Airlines
Deal found 3/28$310
Sat 4/202:37 pmSTL - ONT
1 stop6h 12mAmerican Airlines
Sat 4/2710:00 amONT - STL
1 stop5h 16mAmerican Airlines
Deal found 3/28$358
Tue 4/21:22 pmORD - ONT
1 stop9h 24mAmerican Airlines
Wed 4/311:59 pmONT - ORD
1 stop6h 34mAmerican Airlines
Deal found 3/28$393
Tue 4/25:00 amORD - ONT
2 stops8h 54mAmerican Airlines
Wed 4/311:59 pmONT - ORD
1 stop7h 34mAmerican Airlines
Deal found 3/28$400
Thu 5/166:50 amPIA - ONT
1 stop9h 02mAmerican Airlines
Mon 5/207:40 pmONT - PIA
2 stops13h 23mAmerican Airlines
Deal found 3/28$482
Wed 5/153:40 pmPIA - ONT
1 stop6h 28mAmerican Airlines
Wed 5/2212:50 pmONT - PIA
1 stop6h 17mAmerican Airlines
Deal found 3/28$796
Wed 5/223:40 pmPIA - ONT
1 stop6h 28mAmerican Airlines
Tue 5/289:30 amONT - PIA
2 stops10h 05mAmerican Airlines
Deal found 3/28$801
Sat 4/66:00 amORD - ONT
1 stop7h 50mAmerican Airlines
Sat 4/67:40 pmONT - ORD
1 stop7h 42mAmerican Airlines
Deal found 3/28$819
Fri 4/263:49 pmMLI - ONT
1 stop6h 25mAmerican Airlines
Fri 4/2611:59 pmONT - MLI
2 stops10h 52mAmerican Airlines
Deal found 3/27$988

Cheap Illinois to Ontario flights in March & April 2024

Find cheap flight options from Illinois to Ontario specifically for the months of March and April 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 3,228,805 searches. Prices were last updated on March 29, 2024.
Scroll through some of the best deals on flights from Illinois to Ontario in 2024. If these deals don't appeal to you, be sure to come back soon for more options.
Sat 4/208:04 pmSTL - ONT
1 stop5h 55mFrontier
Fri 4/2612:55 amONT - STL
1 stop6h 52mFrontier
Deal found 3/28$89
Wed 4/248:04 pmSTL - ONT
1 stop12h 22mFrontier
Wed 5/110:49 pmONT - STL
1 stop9h 29mFrontier
Deal found 3/27$90
Sat 4/279:29 pmMDW - ONT
1 stop11h 02mFrontier
Sat 5/47:26 amONT - MDW
1 stop11h 13mFrontier
Deal found 3/28$90
Tue 4/305:01 amMDW - ONT
1 stop10h 00mFrontier
Tue 4/3010:49 pmONT - MDW
1 stop10h 47mFrontier
Deal found 3/28$91
Sat 4/2710:59 pmMDW - ONT
1 stop10h 04mFrontier
Fri 5/312:55 amONT - MDW
1 stop17h 44mFrontier
Deal found 3/28$95
Sat 4/2710:30 amMDW - ONT
1 stop15h 29mFrontier
Tue 4/3010:49 pmONT - MDW
1 stop10h 47mFrontier
Deal found 3/28$96
Sat 4/2710:30 amMDW - ONT
1 stop15h 29mFrontier
Mon 4/2912:59 amONT - MDW
1 stop8h 39mFrontier
Deal found 3/28$97
Sat 4/2012:59 pmSTL - ONT
1 stop6h 00mFrontier
Mon 4/2212:59 amONT - STL
1 stop12h 51mFrontier
Deal found 3/28$98
Tue 4/2310:59 pmMDW - ONT
1 stop10h 09mFrontier
Fri 4/2610:59 pmONT - MDW
1 stop10h 37mFrontier
Deal found 3/28$100

Illinois to Ontario 2024 flight deals

Discover exclusive flight deals for travel between Illinois and Ontario in 2024. Find excellent offers based on user searches. Over the last 7 days, Cheapflights users made 3,228,805 searches. Data last updated March 29, 2024.
Scroll through some of the best deals on flights from Illinois to Ontario in 2024. If these deals don't appeal to you, be sure to come back soon for more options.
Wed 5/158:04 pmSTL - ONT
1 stop5h 55mFrontier
Fri 5/1712:59 amONT - STL
1 stop6h 26mFrontier
Deal found 3/27$76
Sat 4/208:04 pmSTL - ONT
1 stop5h 55mFrontier
Fri 4/2612:55 amONT - STL
1 stop6h 52mFrontier
Deal found 3/28$89
Wed 4/248:04 pmSTL - ONT
1 stop12h 22mFrontier
Wed 5/110:49 pmONT - STL
1 stop9h 29mFrontier
Deal found 3/27$90
Sat 4/279:29 pmMDW - ONT
1 stop11h 02mFrontier
Sat 5/47:26 amONT - MDW
1 stop11h 13mFrontier
Deal found 3/28$90
Tue 4/305:01 amMDW - ONT
1 stop10h 00mFrontier
Tue 4/3010:49 pmONT - MDW
1 stop10h 47mFrontier
Deal found 3/28$91
Thu 5/1610:22 pmMDW - ONT
1 stop27h 37mFrontier
Wed 5/222:35 pmONT - MDW
1 stop28h 52mFrontier
Deal found 3/28$94
Sat 4/2710:59 pmMDW - ONT
1 stop10h 04mFrontier
Fri 5/312:55 amONT - MDW
1 stop17h 44mFrontier
Deal found 3/28$95
Sat 4/2710:30 amMDW - ONT
1 stop15h 29mFrontier
Tue 4/3010:49 pmONT - MDW
1 stop10h 47mFrontier
Deal found 3/28$96
Sat 4/2710:30 amMDW - ONT
1 stop15h 29mFrontier
Mon 4/2912:59 amONT - MDW
1 stop8h 39mFrontier
Deal found 3/28$97

Illinois to Ontario flights leaving soon

Find last-minute flight options from Illinois to Ontario for spontaneous travel. Discover available flights and compare prices based on user searches. Secure great deals and offers for spontaneous trips with quick booking options. Over the last 7 days, Cheapflights users made 3,228,805 searches. Data last updated March 29, 2024.
Have a look at some of the last-minute flights available departing from Illinois to Ontario. To prevent any unwanted surprises, users should verify their flight info before booking.
Fri 4/57:37 pmSTL - ONT
1 stop14h 13mFrontier
Mon 4/2210:59 pmONT - STL
1 stop9h 19mFrontier
Deal found 3/28$145
Thu 4/47:37 pmSTL - ONT
1 stop18h 16mFrontier
Thu 4/115:12 pmONT - STL
1 stop15h 06mFrontier
Deal found 3/28$181
Tue 4/29:14 amMDW - ONT
1 stop16h 55mFrontier
Tue 4/97:27 amONT - MDW
1 stop26h 11mFrontier
Deal found 3/27$212
Thu 4/45:10 amMDW - ONT
1 stop12h 42mFrontier
Thu 4/119:04 pmONT - MDW
1 stop12h 32mFrontier
Deal found 3/27$218
Fri 4/57:37 pmSTL - ONT
1 stop14h 13mFrontier
Mon 4/89:55 pmONT - STL
1 stop10h 28mFrontier
Deal found 3/28$218
Wed 4/39:14 amMDW - ONT
1 stop16h 55mFrontier
Mon 4/87:27 amONT - MDW
1 stop22h 57mFrontier
Deal found 3/27$219
Thu 4/45:10 amMDW - ONT
1 stop12h 42mFrontier
Wed 4/1012:59 amONT - MDW
1 stop16h 16mFrontier
Deal found 3/27$222
Wed 4/35:22 pmMDW - ONT
1 stop16h 28mFrontier
Tue 4/912:59 amONT - MDW
1 stop8h 39mFrontier
Deal found 3/28$226
Thu 4/45:10 amMDW - ONT
1 stop12h 42mFrontier
Mon 4/89:55 pmONT - MDW
1 stop11h 32mFrontier
Deal found 3/28$228

One-way flights to Ontario from Illinois

Search for one-way flight options from Illinois to Ontario. Find affordable one-way fares based on user searches. Compare prices and availability to plan your one-way journey according to your preferred dates and budget. Over the last 7 days, Cheapflights users made 3,228,805 searches. Data last updated March 29, 2024.
Some of the best available deals we've found on one-way flights from Illinois to Ontario. Users in need of a round-trip flight from Illinois to Ontario instead should update the search form at the top of page.
Tue 4/236:27 pmORD - ONT
1 stop7h 32mFrontier
Deal found 3/28$53
Thu 5/211:38 amSTL - ONT
1 stop20h 48mFrontier
Deal found 3/28$55
Tue 4/166:27 pmORD - ONT
1 stop7h 32mFrontier
Deal found 3/28$60
Tue 4/306:27 pmORD - ONT
1 stop7h 32mFrontier
Deal found 3/28$64
Wed 4/246:27 pmORD - ONT
1 stop7h 32mFrontier
Deal found 3/28$65
Wed 5/1512:29 pmORD - ONT
1 stop11h 31mFrontier
Deal found 3/28$66
Sat 4/136:27 pmORD - ONT
1 stop7h 32mFrontier
Deal found 3/28$69
Wed 4/106:27 pmORD - ONT
1 stop7h 32mFrontier
Deal found 3/28$70
Wed 5/156:27 pmORD - ONT
2 stops14h 12mFrontier
Deal found 3/28$71

Find flights from Illinois to Ontario within your budget

Customize your flight search to find flights from Illinois to Ontario that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 3,228,805 searches. Data last updated March 29, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$76 - $287

Route

Depart

Return

Price

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Wed 5/15

1 stop5h 55m

Ontario

Fri 5/17

1 stop6h 26m

$76

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Sat 4/20

1 stop5h 55m

Ontario

Fri 4/26

1 stop6h 52m

$89

Chicago MidwayOntario

MDW - ONT

MDWONT

Chicago Midway

Sat 4/27

1 stop11h 02m

Ontario

Sat 5/4

1 stop11h 13m

$90

Lambert-St LouisOntario

STL - ONT

STLONT

Lambert-St Louis

Wed 4/24

1 stop12h 22m

Ontario

Wed 5/1

1 stop9h 29m

$90

Chicago MidwayOntario

MDW - ONT

MDWONT

Chicago Midway

Tue 4/30

1 stop10h 00m

Ontario

Tue 4/30

1 stop10h 47m

$91

Chicago MidwayOntario

MDW - ONT

MDWONT

Chicago Midway

Thu 5/16

1 stop27h 37m

Ontario

Wed 5/22

1 stop28h 52m

$94

Chicago MidwayOntario

MDW - ONT

MDWONT

Chicago Midway

Sat 4/27

1 stop10h 04m

Ontario

Fri 5/3

1 stop17h 44m

$95

Chicago O'Hare IntlOntario

ORD - ONT

ORDONT

Chicago O'Hare Intl

Sat 4/27

1 stop7h 32m

Ontario

Sat 5/4

2 stops10h 33m

$174

Moline Quad-CityOntario

MLI - ONT

MLIONT

Moline Quad-City

Sat 4/27

1 stop7h 22m

Ontario

Tue 4/30

1 stop8h 07m

$287

Flights are sorted by cheapest first

Deals found on 3/27

No data available for this route at this time. Please check back soon.

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Ontario. Reviews last updated March 29, 2024.
Get a feel of what it's like to fly with Frontier, American Airlines and Alaska Airlines from Illinois to Ontario by reading reviews from past customers. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
8.1
Very good
9,127 reviews

Overall

8.1

Entertainment

7.4

Boarding

8.2

Food

7.3

Crew

8.6

Comfort

7.9

Reviews

1 / 10

I would have liked flying out of the airport I chose not a different airport. My flight was moved to San Jose

8.1
Very good
9,127 reviews
8.1
Very good
9,127 reviews

Overall

8.1

Entertainment

7.4

Boarding

8.2

Food

7.3

Crew

8.6

Comfort

7.9

Reviews

1 / 10

I would have liked flying out of the airport I chose not a different airport. My flight was moved to San Jose

8.1
Very good
11,402 reviews
8.1
Very good
9,127 reviews

Overall

8.1

Entertainment

7.4

Boarding

8.2

Food

7.3

Crew

8.6

Comfort

7.9

Reviews

1 / 10

I would have liked flying out of the airport I chose not a different airport. My flight was moved to San Jose

7.4
Good
11,481 reviews
8.1
Very good
9,127 reviews

Overall

8.1

Entertainment

7.4

Boarding

8.2

Food

7.3

Crew

8.6

Comfort

7.9

Reviews

1 / 10

I would have liked flying out of the airport I chose not a different airport. My flight was moved to San Jose

7.3
Good
15,181 reviews
8.1
Very good
9,127 reviews

Overall

8.1

Entertainment

7.4

Boarding

8.2

Food

7.3

Crew

8.6

Comfort

7.9

Reviews

1 / 10

I would have liked flying out of the airport I chose not a different airport. My flight was moved to San Jose

6.7
Okay
1,593 reviews
8.1
Very good
9,127 reviews

Overall

8.1

Entertainment

7.4

Boarding

8.2

Food

7.3

Crew

8.6

Comfort

7.9

Reviews

1 / 10

I would have liked flying out of the airport I chose not a different airport. My flight was moved to San Jose

Related info for your journey

Find useful and relevant information for your journey from Illinois to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • What airport do you fly into for flights to Ontario from Illinois?

    Located just 3.1 mi from the city center, Ontario (ONT) is the airport most travelers will use when flying to Ontario from Illinois.

  • Can I find flights from Illinois to Ontario for under $100 on Cheapflights?

    Yes, there are multiple flights from Illinois to Ontario for under $100. The cheapest flight booked recently is on Frontier for just $76, but on average you can expect to pay $96.

  • Are there last-minute flights available from Illinois to Ontario for under $200?

    There are currently 20+ open flights from Illinois to Ontario within the next 7 days for less than $200.

  • What are the most popular routes from Illinois to Ontario?

  • What are the most popular airlines that fly from Illinois to Ontario?

  • What does ORD to ONT mean?

    ORD and ONT are unique codes to identify airports used in the aviation industry. They are defined by IATA (International Air Transport Association) and are commonly called IATA codes. ORD to ONT refers to a flight route from Chicago O'Hare Intl Airport to Ontario Airport. This flight route has multiple associated airports, so we think it might be helpful to learn the name and codes of them as well. They are Chicago Midway Airport (MDW), Moline Quad-City Airport (MLI), Greater Peoria Airport (PIA), Bloomington-Normal Airport (BMI), Champaign University-Willard Airport (CMI).

  • Can I find deals for flights from Illinois to Ontario that include extra baggage allowance?

    The amount of baggage you can bring depends on the airline and the type of fare you've chosen. After entering your flight details, you'll be able to view the specific baggage policies for each deal in the search results. Keep in mind that certain deals may offer additional baggage allowance.

  • Can I find deals on flights from Illinois to Ontario with specific airlines?

    Yes, Cheapflights allows you to browse and filter flight deals by airline. After entering your origin and destination, use the available filters to view flights offered by airlines.

  • Can I find deals for flights from Illinois to Ontario that include hotel bookings?

    Yes. In addition to deals on Illinois to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Illinois to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to see available direct flights.

  • Can I find deals for business class flights from Illinois to Ontario?

    Yes. Cheapflights offers flight deals from Illinois to Ontario by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • Can I find deals for flights from Illinois to Ontario that allow pets onboard?

    Many airlines do offer the option to travel with pets. After selecting a flight deal, you can find more information about the airline's pet policy on their official website or by contacting the airline directly. Please note that additional fees and restrictions may apply.

  • How recently were the Illinois to Ontario flight deals updated?

    The Illinois to Ontario flight deals you see on this page were last updated on 3/28.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Illinois to Ontario
See prices for flight routes from nearby airports that may be better suited for you.

Top 5 airlines flying from Illinois to Ontario

Discover the top 5 airlines that operate flights from Illinois to Ontario. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 3,228,805 searches. Data last updated March 29, 2024.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$120Average$250FlexibilityNo cancel feeOn-time62%
Search Frontier flights
Spirit AirlinesCheapest$131Average$260FlexibilityNo cancel feeOn-time65%
Search Spirit Airlines flights
DeltaCheapest$276Average$431FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
United AirlinesCheapest$330Average$491FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
American AirlinesCheapest$331Average$587FlexibilityNo cancel feeOn-time71%
Search American Airlines flights

Search flights from Illinois to Ontario by cabin class

Find flights from Illinois to Ontario, based on your preferred cabin class, be it economy, premium economy, business, or first class.

Hourly flight availability from Illinois to Ontario

Find hourly flight availability from Illinois to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 29, 2024.
0%of flight departuresEarly morningMidnight to 6 am
100%of flight departuresMorning6 am to noon
0%of flight departuresAfternoonNoon to 6 pm
0%of flight departuresEvening6 pm to midnight
Midnight
6 AM
Noon
6 PM

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travelers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Illinois to Ontario?

When you search for this flight from Illinois to Ontario, Cheapflights searches on 900+ travel sites to save you time finding great flight deals online. Additionally, we offer filter features so you can choose a preferred cabin class or airline, see different price ranges, and much more so you can book the flight for you.

Why should you use Cheapflights to find cheap flight tickets from Illinois to Ontario?

Cheapflights simply makes it quick and affordable to book flights from Illinois to Ontario by bringing together all flight options from hundreds of airlines and agencies online — and put it in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

Can Cheapflights find flights from Illinois to Ontario with no change fees?

Cheapflights does show flights with no change fees to all users. To see these options for flights from Illinois to Ontario, users can toggle the no change fees filter when performing a flight search.

Can Cheapflights notify me if prices for flights from Illinois to Ontario become cheaper?

Yes, Cheapflights offers price alerts on Illinois to Ontario flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

Can I find deals on last-minute flights from Illinois to Ontario?

Yes, you can often find last-minute deals on Illinois to Ontario flights on Cheapflights. However, these deals can vary and may not always be available. We recommend checking back frequently or signing up for price alerts for the most up-to-date deals.

How can I compare prices from different travel booking sites for flights from Illinois to Ontario?

Cheapflights aggregates prices from various travel booking sites. This allows you to compare prices and choose the best deal.

Can I find deals for flights from Illinois to Ontario that offer flexible cancellation policies?

Cancellation policies vary by airline and fare type. After entering your flight details, you can view the cancellation policies for each deal in the search results. Some deals may offer flexibility in terms of cancellation and changes.

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